Engine starting device



Feb. 6, 1951 BOYCE 2,540,607

ENGINE STARTING DEVICE Filed June 15, 1945 3 Sheets-Sheet 1 53 2 4 I?'/a 39 25 z? INVENTOR. LEONARD D. BOYCE Feb. 6, 1951 L. D. BOYCE ENGINESTARTING DEVICE 3 Sheets-Sheet 2 INVENTOR. LEONARD D. BOYCE Filed June15, 1945 3 Sheets-Sheet 5 F l G. 6

L. D. BOYCE ENGINE STARTING DEVICE F I G. 7.

Feb. 6, 1951 Filed June 15, 1945 INVENTOR. LEONARD D. BOYCE gatentedFeb. 6,. 1 951 1 UNITED STATES PATENT OFF-ICE ENGINE STARTING Leonard D.Boyce, Richmond Heights, Mo., as-

s'ignor to 'Carter Carburetor Corporation, St.

Louis,'Mo., a corporation of Delaware 7 Application June 15,1945, SerialNo. 599,658

cilitate startingof the engine. In'most of these i the choke valve isurged towards closed position i when the temperature is low by athermostat.

In. one example, a relatively strong thermostat 'is used and its forceis counteracted by a suction responsive element, when'the engine startsto 12 Claims. (01. 261-49 devices for run under its own power, toadmitproper air sup- 7 'ply.- Such ,a jdevice'is' illustrated in CoffeyPatent No."2,085,351. In others, the choke is locked H a in fullclosedposition before the engine starts to run and, afterwards, the lock isbroken to re- 'lease.'the choke for control by the thermostat. Insomecas'es', it is desirable that a thermostatic choke valve be lockedin its assumed position ac- Fig. 5 is a section similar to'Flg. 4 butshowing-- Fig. '1 is a detail section similar to Fig. '41b1 1t showingthe structure of Fig. -*6 with the choke opened slightlyby enginesuction. v Fig. 8 is aview similar to Fig. 7', but with the 1 partsinthe funloading" position;

Fig; 9 is a similar view showing the choke locked in a partially openpositionfor starting.

Fig. 1 shows an internaljcombustion engine 8 of the automotive typehaving an exhaust manifold 9 and an intake manifold In to which isattached a carburetor generally indicated at H. The carburetor throttleis operated in the usual manner by linkage l2 extending to throttlepedal cording to temperature durin cranking. However, it'ls alsovdeslrable'that the valve be free to close at'all times .under theinfiuenceofthe cool- 'ing'thermostat. 4 'Accordingly, it isans-objectof. the present invention to provide a novel choke control device whichcan be locked insubstantiallyany position during ,crankingaccording totemperature, but whichflisfreeto respond to" the thermostat whentheengine isnot r'uiming.

cefwhichis normally urged towards its locking .positiom but which iswithdrawn therefrom when f mi-isp'also-withdrawn therefrom whenever thedevice adapted-"to 160mm choke in its assumed .positi'on"fo'r startingand also incorporating an funloader forlcausing partial-opening of thechoke. when the throttle is fully opened.

. 'Another'object'istoprovide stake-camellia l3 located'conveniently forthe driver." A starting motor M is located in position for cooperating"with the fly-wheel located in the housin IS in "starting the engine.

Fig. 2 shows a carburetor with a somewhat simstant level chamber I8-fromwhich fuel is supp'liedto the barrelthrough main nozzle l9. Entry ,ofair. into the upper part ofthe barrel is controlled by anunbalanced,-.butterfiy choke valve 20 one shaft lljournaled in the wallof the upper or 'airhorn portion 22 of the barrel. Choke valve 320carriesa yieldingly mountedpoppet valve 23 which may be opened by}enginesuction, as de- 1 scribed hereafter. A coiled, 'bi-metalthermostat 24; has one end hooked around a fixed stop 250n-the alrhornand the other end anchored in an extremity of choker shaft 2|. Thethermostat ismounted so as to urge the choker valve 'close'dat lowtemperatures; A throttle 26 controls the discharg'e' -of mixture fromthe lower end of the barrel.

A quadrant 21, carried rigidly by the choker 1 "r rh se objects andother detailed objects here- 1 after appearing-are attainedsubstantially by the. H

'in'which i l I "'Flg.;1- is-aview .of an internal combustion eng'ineand carburetor ,lthereto. I 1 e a I g Z 'i's' a somewhat'diagrammaticsectionaljyiewillustrating a' form of the invention. Fig; 3 :is a viewsimilar toFig. 2 but showing '-a diflerent form of the invention."

device -'illustrated in the accompanying drawings ".Fig; .4is'adetail'fse'ction taken substantially on Q having the invention'appliedshaft, has a series of pheripheral teeth 28.

Mounted on the air horn and. projecting laterally therefrom is acylinder 29 in. which works a pistonv 30 constantly urged to'the rightby a coiled spring 3'l; A locking finger 32' -projects rightwardlyfrompiston 30 and has'a point 33 for .co operating with the adjacent teeth28 to lock .quadrant 26 andthe choke valve. A tube 34 connects the lefthand end of cylinder 21 to a. port 35 opening into the mixture 'barrelposterior to throttle '26. Cylinder 28, thus, communicates with enginesuction through port 35.

- A cam segment 36 is rigidly carriedby the throttle shaft andcooperates with a follower rod 31 slidable in guides 38 and 33. The uppr extremity of rod 31 extends within cylinder 28 so as to-iimit therightward movement of piston 30. when throttle 26 is moved to its fullyclosed position, a high point 4| on cam 33 enga es rod 31 so as to pushthe rod upwardly and shift piston 30 and pointed pin or detent 33 totheleft or away from locking quadrant 21 so as to release the choke valve.Likewise, when the throttle is in substantially wide open position,another high point 42 on cam 36 insures retraction of detent 33. The camhas a low portion 43 between the extreme high points.

This device operates as follows:

Assuming the engine is to be started at a low temperature and that thethrottle valve is in its normal, closed position, thermostat 24 willhave urged choker valve 20 fully closed, as shown in Fig. 2; Throttlevalve 26 is then slightly opened, as is desirable for starting, to bringintermediate low portion 43 of the cam in line with rod I '31,permitting this rod to drop. Thereupon,

locking pin 3! is urged rightwardly by spring.\30 into locking positionwith quadrant 26. The starter motor is then operated to crank theengine. The cranking suctions, however, do not effect either choker 20or poppet 23. When the enginefires and starts to run under its ownpower, the sharply increased suction forces open poppet 23 to supplynecessary additional air. Almost simultaneously, piston 30 is drawn tothe left so as to unlock toothed quadrant 21. Thereafter, the chokevalve is under the control of the thermostat and the direct action ofsuction thereon. After the engine has reached normal temperature, choke20 will be fully open and will remain in that position irrespective ofsuction, until the engine again cools below its normal temperature.

When the engine is allowed to stand. idle after a run, the return of thethrottle to its normal, close position will release the toothed quadrantso that the choke valve may freely close under the influence of thethermostat.

Figs. 3, 4, and shows a structurally different form of the invention inwhich the various choke control parts are mounted in a cylindricalhousing 50 as in Fig. 1, adjacent the carburetor air horn 22a.Thermostat 24a is anchored at the .center to cover 5| of the casing andhas a hook 52 at its outer extremity receiving an L-shaped arm 53 whichis rigidly attached tochoker shaft 2la. Toothed quadrant 21a is alsorigid with this shaft and positioned to be engaged by a pointedextension or detent 33a on suction piston 30a. Asshown, quadrant 21aforms an extension of L-shaped lever 53.

A sleeve 54 is loosely received on choke shaft 2ia,.between the air hornand casing 50 and carries a cam 36a within housing 50. Also rigid withthe sleeve between the housing and the air horn is a lever 55 which isconnected by a link 56 to an arm 51 rigid with the throttle shaft. Uponclosing of the throttle, high point 41a of cam quadrant 38a engages thetop of piston 30a to forcev it and locking point 33a downwardly andclear of toothed segment 21a. Point 33a is also released by suction, asin the previous form, when the engine starts to run under its own power..When the choke valve is fully opened, as in Fig. 4, a second high point42a on the cam engages the top of piston 30a and again releases lockingsegment 21a. In any intermediate positions of the throttle, segment 21aand the choke valve will be locked by pointed'element 33a whenever theengine is stopped. Thus, necessarib', the choke will beheld firmlyduring cranking, in whatever position it has assumed .under theinfluence of the thermostat provided the throttle is between fully openand fully closed position.

The formin Figs. 34. and 5 aiso shows a stove 60 mounted on exhaustmanifold 9 and connected by a tube 3| to a boss 62 on housing T system,generally indicated at 64 'and a metering pin 65 connected to thethrottle by lever 66 and link 61. v

The operation of the form in Figs. 3, 4, and 5 is-the same as that inFig. 2, corresponding parts being given the same reference numerals withthe letter 41" added.

The form i i-Figs. 7-9, inclusive, incorporates the features of theprevious two forms, with the addition of "unloader mechanism. Suctionpiston 3% has pinned thereto, at one side of looking point 332;, anangular arm 10 having a curved slot 1|. Toothed segment 21b, rigid withchoke shaft 2"), has a laterally projecting pin 12 received in slot 1|.As in the previous form, an' arm 55b, movable with cam 36b, is rotatableon the choke shaft and is connected by a link m 56b to throttle arm51?).

This form operates the same as the previous form except for the unloaderconnection by means of which cam 36b is rotated to the position in Fig.8, when the throttle valve issubstantially fully opened, to depresspiston 30b.

At the same time, the upper edge of slot 1 engages pin 12 to move thetoothed segment and the choke valve slightly. in the clockwise direction so as to openthe valve. In this position, continued cranking of theengine will draw air through the carburetor and manifold to sweep outexcess fuel therein. The unloaden' elements do not affect the otheroperations of the mechanism, as previously described.

In all of the forms, means is provided to insure locking of the chokevalve, in whatever position it has assumed in accordance with thetemperature, as soon as the throttle is opened to the starting positionto release detent carrying piston 30, 3041, or 30b. In case the chokervalve is locked tightly closed in starting, the poppet valve thereinwill open as soon as the engine fires to supply necessary additionalair. A fixed air hole may also be provided in the choke valve, as shownin the last two forms. This form of choke control has been found tostart more satisfacte:lly with certain engines than other types atpresent known.

The invention may be modified as will occur to those skilled in the artand the exclusive use of all such modifications as come within the scopeof the appended claims is contemplated.

I claim: v

1. A starting device for an internal combustion engine having a mixtureconduit comprising a choke valve, a thermostat for moving said cho evalve towards closed position when the tem v ture is low, a membermovable rigidly with i choke valve, an element for engaging said mem---ber in substantially any position of said choke valve to lock the same,means constantly urging said element into locking relationship with said2. ,A starting device for an internal combustion I engine having a fuelsupply conduit and a throttle J therein comprising a valve in saidconduit for enriching the'mixture, a thermostat for moving said valvetoward mixture enriching position when the temperature is low, anelement capable of-locksaid valve in substantially any position thereof.means normally urging said element into looking position with relationto. said valve, and suction responsive means for withdrawing saidelement from said locking position.

3.A starting device for an internal combustion engine having a supplyconduit for fuel and air. mixture and a throttle therein comprisin achoke valve in said conduit for enriching the mixture, 'a thermostat formoving said valve toward mixture enriching position whenthe temperatureis low, cooperating elements for locking said valve one of which ismovable rigidly with said choke valve, means normally urging said otherlocking element into locking relationship with said first element, andmeans responsive to engine suction produced when the engine starts torun under its own power for withdrawing said other-element from saidlockin relationship.

4. A starting device for an internal combustion engine having a supplyconduit for fuel and air mixture and a throttle therein comprising achoke valve in said conduit for enriching the mixture, a thermostat formoving said valve toward mixture enriching position when" thetemperature is low, cooperating elements, including a first elementrigidly movable with said choke valve capable of locking said valve insubstantially any position thereof, means normally urging the other ofsaid elements into locking relationship with said first element, andmeans responsive to engine suction for withdrawing said other elementfrom said locking relationship, said valve being constructed andarranged to move to and remain in its lean position during normaltemperature operation.

5. A starting device for an internal combustion engine having a supplyconduit for fuel and air mixture and a throttle therein comprising achoke valve in said conduit for enriching the mixture, a thermostat formoving said valve toward mixture enriching position when the temperatureis low,

cooperating elements. including a first element rigidly movable withsaid choke valve for locking said valve, means normally urging the otherof said elements into locking relationship with said first element,suction responsive means for withdrawing said other element from saidlocking position, and means associated with said throttle forwithdrawing said other element from said locking relationship when thethrottle is closed.

6. A starting device for an internal combustion engine having a supplyconduit for fuel and air mixture and a throttle therein comprising avalve in said conduit for enriching the mixture, a thermostat for movingsaid valve toward mixture enriching position when the temperature islow, cooperating elements capable of locking said valve inanyintermediately open position thereof ineluding a first elementmovable with said valve, means normally urging the second of said'elements into locking relationship with said first element. suctionresponsive means for withdrawing said second element from said lockingposition. and means associated with said throttle for withdrawing one ofsaid elements from said locking 6 relationship when the throttle issubstantially opened.

7. A starting device for arr-internal combustion engine having a supplyconduit for fuel and air mixture and a throttle therein comprising anunbalanced choke valve in the air inlet of said conduit. a thermostatfor moving said valve toward mixture enriching position when thetemperature is low, cooperating elements for locking said valve insubstantially any assumed position when the engine is not in operationincluding a first element rigidly movable with said valve, meansnormally urging a second of said elements into look-- ing relationshipwith said first element, a poppet valve yieldingiy carried by said chokevalve and openable by engine suction when said choke valve is lockedclosed, suction responsive means for withdrawing said second lockinelement from said locking relationship, and throttlev actuated means forwithdrawing said second element from said locking relationship when saidthrottle is closed, said choke valve being constructed and arranged tomove to and remain in fully open position when the engine is at normaloperating temperature. v p 8. A starting device foran internalcombustion engine having a mixture conduit with choke and throttlevalves therein comprising a thermostat for moving said choke'valvetoward mixture enriching position when the temperature is low, a membermovable with said choke valve, an element for engaging said member insubstantially any assumed position of said choke valve when the engineis not in operation to lock said choke valve, a spring normally urgingsaid element into locking relationship with said member, a devicemovable responsive to'engine suction when the engine starts to operateunder its own power for withdrawing said element from lookingrelationship with said member, and a mechanical connection between saidelement and said throttle 9. A starting device for an internalcombustion engine having aninduction conduit with choke and throttlevalves therein, a thermostat for moving said choke valve toward closedposition when the temperature is low, cooperating elements capable oflocking said choke valve in any intermediately open position thereof,and including a first element movable with said choke valve, meansnormally urging a second of said elements into locking relationship withsaid first element. and means for withdrawing said second element fromsaid locking relationship responsive to movement of said throttlevalve-to its fully opened position. a

10. A starting device for an internal combustion engine having aninduction conduit with choke and throttle valves therein, a thermostatfor moving said choke valve toward closed.p0sition when the temperatureis low, cooperating elements capable of locking said valve in anyintermediately open position thereof and including a firstelement.movable withsaid choke valve. means normally urging a second ofsaid elements into locking relationship with said first element, meansresponsive to suction when the engine starts to operate under its ownpower for withdrawingsaid second element from said locking relationship,and additional means for withdrawing said element from said lockingposition when said throttle valve is in substantially fully open orfully closed position.

11. A starting device for an internal combustlon engine having aninduction conduit with choke and throttle valves therein, a thermostatfor moving said choke valve toward closed position when the temperatureis low, cooperating elements capable of locking said valve in anyintermediately open position thereof and including a first elementmovable with said choke valve, means normally urging a second of saidelements into locking relationship with said first element, meansresponsive to suction when the engine starts to operate under its ownpower for withdrawing said second element from said lockingrelationship, and means for forcing said choke open upon substantiallyfull opening of said throttle valve.

12. A starting device for an internal combustion engine having aninduction conduit with choke and throttle valves therein, a thermostatfor moving said choke valve toward closed position when the temperatureis low, cooperating elements capable of locking said valve insubstantially any intermediately open position therechoke valve.

LEONARD D. BOYCE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,215,682 Winkler Sept. 24, 19402,394,665 Christian Feb. 12, 1946 Hunt July 9, 1946

